Slide 1

Case 10 New Frontiers in Pathology, 2009 William G. Finn, M.D. University of Michigan Slide 2 History A 3-month-old girl was referred to the pediatric hematology-oncology service for persistent neutropenia. She had been born premature at 32 weeks gestation, with time in NICU. At birth she had a white blood cell count of 9x10 9 /L and an absolute neutrophil count of 1.5x10 9 /L (both within reference range). Over the following 3 months her neutrophil count decreased to as low as 0.5x10 9 /L. A bone marrow aspiration was performed. Slide 3 Slide 4 Slide 5 Slide 6 Findings Acquired anemia/ neutropenia in an infant Numerous immature cells in marrow Leukemia? Slide 7 Acute Leukemia in Children Signs and symptoms (variable among patients) Fatigue Pallor Petechiae Cytopenias Organomegaly Lymphadenopathy Slide 8 Leukemia? Pros Persistent idiopathic cytopenias (neutropenia, anemia) Marked increase in immature cells in marrow (>20%) Cons Normal platelet count No leukocytosis (O.K. for A.L.L. but uncommon in infant A.L.L.) Clinically stable, not acutely ill Slide 9 Our Patient A.L.L. Slide 10 Flow Cytometry B-A.L.L. in children: CD19+, CD10+, CD20+/-, CD22+/-, CD34+/-, CD38+, TdT+ Slide 11 Flow Cytometry Our patient: CD19+, CD10+, CD20+/-, CD22+/-, CD34+/-, CD38+, TdT+ Slide 12 Flow Cytometry A.L.L. CD45 Side Scatter CD33 CD34 CD19 CD10 Slide 13 Flow Cytometry A.L.L. CD45 Side Scatter CD19 CD38 CD5 CD20 Slide 14 Flow Cytometry Our Patient CD45 Side Scatter CD33 CD34 CD19 CD10 Slide 15 Flow Cytometry Our Patient CD45 Side Scatter CD19 CD38 CD5 CD20 Slide 16 Slide 17 Flow Cytometry Our Patient CD45 Side Scatter CD33 CD34 CD19 CD10 Slide 18 Flow Cytometry Our Patient CD45 Side Scatter CD19 CD38 CD5 CD20 Slide 19 Flow Cytometry Our Patient Side Scatter CD45 CD33 CD34 CD19 CD10 Slide 20 Flow Cytometry Our Patient Side Scatter CD45 CD19 CD38 CD5 CD20 Slide 21 Diagnosis Hematogone Hyperplasia Slide 22 Hematogones Physiologic B-cell precursors Mystery Cells Normal counterpart to B-precursor lymphoblasts Substantially resemble leukemic lymphoblasts, both morphologically and immunophenotypically Slide 23 Hematogones Proliferate in a variety of reactive states, most notably in children Autoimmune cytopenias (ITP, etc) Recovery from chemotherapy (including A.L.L. therapy) Hematogone hyperplasia usually